-
1
Melt 1 tablespoon of the butter in a large frying pan over medium heat.
-
2
When the foaming subsides, add onion and cook, stirring occasionally, until softened, about 4 minutes.
-
3
Remove from heat and let cool slightly.
-
4
Meanwhile, place bread in the bowl of a stand mixer fitted with a paddle attachment and add milk.
-
5
Let sit until the bread has absorbed the milk, about 5 minutes.
-
6
Add the cooled onion, ground beef and veal, egg, salt, pepper, and nutmeg and beat on medium speed until the mixture is light in color and appears sticky, about 5 minutes.
-
7
Fill a medium bowl with water.
-
8
Form the meat mixture into 1-inch balls, wetting your hands in the bowl of water as necessary to keep the mixture from sticking, and place meatballs on a baking sheet.
-
9
Wipe the frying pan clean with a paper towel.
-
10
Melt the remaining 2 tablespoons butter in the pan over medium heat.
-
11
When the foaming subsides, add half of the meatballs and fry, turning occasionally, until browned on all sides and cooked through, about 8 to 10 minutes.
-
12
Transfer to a clean serving dish; set aside.
-
13
Repeat with remaining meatballs.
-
14
Sprinkle flour over the drippings in the pan and whisk, scraping up any browned bits, until the flours no longer raw tasting, about 1 minute.
-
15
Slowly pour in broth, whisking as you do to smooth out any lumps.
-
16
Cook until the mixture starts to boil and thicken, about 3 minutes.
-
17
Strain through a fine-mesh strainer into a medium heatproof bowl and discard the solids.
-
18
Transfer the strained sauce back to the pan.
-
19
Reduce heat to low and whisk in sour cream.
-
20
Season with salt and pepper as needed.
-
21
Return meatballs to the pan until heated through, about 5 minutes.
-
22
Transfer meatballs and sauce to the serving dish and sprinkle with parsley.
